Before I talk about Sherlock Holmes, I’m going to talk about my favourite moment in Metal Gear Solid 3: Snake Eater. It’s the most lauded game in a series a dozen titles long, each one full of the maddest stuff you wouldn’t believe. Comedy ghosts and philosopher warriors and soviet space magic. And the best bit is when Snake climbs up a ladder while music plays.

If you’ve played the game you know what I mean, but for those who haven’t here’s the story. You’ve just finished up this immense sniper battle with The End, the oldest and weirdest of the foreshadowed boss characters. It was spread across several densely-packed forested areas, each one enormous and scattered throughout with viable sniping spots that both you and the old bastard cycle through in vying for an upper hand. You can win in any number of ways – you can poison him, stealth him, outwit him, track him, goad him, outwait him, or snipe him hours before the battle even begins and bypass the whole affair. It is the perfect ‘systems’ moment where all these mechanical aspects thread together in one beautiful tapestry from which the player traces their own narrative of strategy and improvisation.

Once it’s done, the forest exit opens up and you can progress to the next area. You know you still have two more foreshadowed bosses to go, plus the three major antagonistic characters, plus the mechanical behemoth Shagohod that is ostensibly (but not actually) the story’s McGuffin. The End was exhausting and invigorating but, finally, you’re halfway there.